Method and device for forming a film on substrate surface and formed film

Abstract

The present application relates to the field of semiconductor technology, and specifically to a method for forming a film on a substrate surface, comprising the following steps: gasifying a precursor into a precursor vapor; in the process of transporting the precursor vapor into a deposition chamber, increasing the gas supply flow rate of the precursor vapor by first compressing and then expanding it, so as to form a film with uniform thickness on the substrate surface of the deposition chamber. By increasing the gas supply flow rate of the precursor vapor, the precursor vapor can be transported to the center of the substrate and the top area of ​​the deposition chamber, avoiding insufficient supply of the precursor vapor in the center of the substrate, thereby forming a film with uniform thickness on the substrate surface of the deposition chamber.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a method and device for forming a film on a substrate surface and the formed film. Background Art

[0002] In the Atomic Layer Deposition (ALD) process with a conventional furnace structure, when feeding into the deposition chamber, the three-way valve located at the rear end of the evaporation device and connected to it is always in an open state. Due to the high viscosity of the precursor, sufficient material cannot be introduced into the center of the substrate, resulting in uneven thickness distribution between the center and edge of the film on the substrate, which in turn affects the electrical properties of the film (such as a dielectric film) and causes leakage current problems. Summary of the invention

[0003] The present application solves the above technical problems in the related art at least to some extent. To this end, the present application proposes a method and device for forming a film on a substrate surface and the formed film, which solves the problem of uneven thickness distribution between the center and the edge of the film on the substrate.

[0004] In order to achieve the above-mentioned object, the first aspect of the present application provides a method for forming a film on a substrate surface, comprising the following steps:

[0005] vaporizing a precursor into a precursor vapor;

[0006] In the process of conveying the precursor vapor into the deposition chamber, the gas supply flow rate of the precursor vapor is increased by first compressing and then expanding, so as to form a film with uniform thickness on the substrate surface of the deposition chamber.

[0007] A second aspect of the present application provides a device for forming a film on a substrate surface, comprising:

[0008] A gasification device, used for gasifying the precursor into precursor vapor;

[0009] a deposition chamber, in which a substrate is disposed, for receiving the precursor vapor and depositing the precursor vapor on the substrate;

[0010] A flow control valve is located between the vaporization device and the deposition chamber. The precursor vapor flows into the deposition chamber through the flow control valve. The flow control valve is used to adjust the gas supply flow of the precursor vapor. The flow control valve is closed for a period of time and then opened again during the process of the vaporizer conveying the precursor vapor to the deposition chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0012] Figure 1 A schematic diagram of a partial structure of an apparatus for forming a film on a substrate surface in some embodiments of the present application;

[0013] Figure 2 A comparison diagram of the film thickness distribution formed on the substrate surface by the present application and the prior art;

[0014] Figure 3 For some embodiments of the present application, a capacitance distribution diagram of a film formed at different locations on a substrate surface is provided. DETAILED DESCRIPTION

[0015] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0016] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0017] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element or an intervening layer / element may exist therebetween. In addition, if a layer / element is "on" another layer / element in one orientation, the layer / element may be "below" the other layer / element when the orientation is reversed.

[0018] Films (e.g., dielectric films, semiconductor films, insulating films, and metal films) can be formed during the production of semiconductor devices. The process of forming the film includes atomic layer deposition (ALD). According to the deposition process, the process material is placed in an environment of atomic layer deposition vapor, such as an organic metal compound. The atomic layer deposition vapor adsorbed on the material is decomposed by exposure to light energy or thermal energy. Therefore, a film (e.g., a semiconductor film, a dielectric film, or a metal film) can be formed on the surface of the material. One of the key elements of the atomic layer deposition process includes an evaporation device, which evaporates a liquid precursor into the form of a chemical vapor deposition vapor and transports the atomic layer deposition vapor to an atomic layer deposition chamber. When the atomic layer deposition vapor contacts a substrate heated in the atomic layer deposition chamber, the atomic layer deposition vapor reacts on the substrate and forms a film.

[0019] An embodiment of one aspect of the present application relates to a method for forming a film on a substrate surface, comprising the following steps:

[0020] A substrate is provided and placed in a deposition chamber. In this embodiment, the substrate is preferably a semiconductor substrate, for example, a bulk silicon semiconductor substrate, a silicon-on-insulator (SOI) semiconductor substrate, a germanium semiconductor substrate, a germanium-on-insulator (GOI) semiconductor substrate, a silicon-germanium semiconductor substrate, a III-V compound semiconductor substrate, or an epitaxial thin film semiconductor substrate obtained by performing selective epitaxial growth (SEG).

[0021] When the semiconductor substrate is a silicon-based semiconductor substrate, the semiconductor substrate may include, for example, dangling bonded silicon atoms that are not bonded to oxygen ions. The operating characteristics of the transistor may be stabilized by a hydrogen annealing process, through which hydrogen atoms are bonded to the dangling bonded silicon atoms of the semiconductor substrate. In this case, the hydrogen atoms may be easily separated from the silicon atoms, but boron may increase the binding energy between the silicon atoms and the hydrogen atoms. Therefore, the variable retention time or charge retention time of the capacitor may be improved.

[0022] Next, the precursor is placed in a vaporization device to be heated and vaporized into precursor vapor. The vaporization device can be selected from any one of a vaporizer, a bubbler or a roaster. In this embodiment, the vaporization device is selected from a vaporizer.

[0023] Next, the precursor vapor is transported into the deposition chamber. During this process, the switch for transporting the precursor vapor into the deposition chamber is turned off, maintained for a period of time, and then turned on again. Specifically, Figure 2 , 3As shown in FIG. 1 , compared with the switch being turned on all the time, the precursor vapor in this embodiment is compressed and expanded during the period when the switch is turned off and on, thereby increasing the gas flow rate of the precursor vapor. In this way, the precursor vapor can be transported to the center of the substrate and the top area of ​​the deposition chamber, thereby avoiding insufficient supply of the precursor vapor in the center of the substrate, thereby forming a film with uniform thickness on the substrate surface in the deposition chamber (such as Figure 2 ), thus improving the electrical properties of the film (as shown Figure 3 As shown), such as dielectric constant, leakage current and other issues. In this embodiment, a vaporizer is used to vaporize the precursor into precursor vapor. A flow control valve is provided between the vaporizer and the deposition chamber. The precursor vapor flows into the deposition chamber through the flow control valve. The flow control valve is closed for 2 seconds and then opened again, thereby increasing the gas supply flow of the precursor vapor.

[0024] It is worth mentioning that the closing time of the flow control valve can also be 1 second, 3 seconds, etc. This embodiment does not limit this, and those skilled in the art can flexibly select it according to their needs.

[0025] In addition, the precursor vapor can be deposited on the substrate in an atomic layer deposition manner to form a film. However, this embodiment is not limited here, and the precursor vapor can also be deposited on the substrate in a manner such as atmospheric pressure chemical vapor deposition (atmospheric pressure CVD), low-pressure chemical vapor deposition (low-pressure CVD), ultrahigh vacuum chemical vapor deposition (ultrahigh vacuum CVD), plasma-enhanced chemical vapor deposition (plasma-enhanced CVD), atomic layer deposition (atomic layer deposition, ALD), and metallo-organic chemical vapor deposition (metallo-organic CVD).

[0026] The film formed on the substrate by the above method can be a dielectric film, and the thickness distribution at the center and the edge is uniform. Specifically, the material of the film is selected from any one or a combination of multiple components of HfO2, ZrO2, TiO2, Nb2O5, Al2O3 and SiO2.

[0027] like Figure 1 As shown, an embodiment of another aspect of the present application relates to a device 100 for forming a film on a substrate surface, comprising:

[0028] The gasification device 10 is used to gasify the precursor into precursor vapor; specifically, the gasification device 10 can be selected from any one of: a gasifier, a bubbler or a baker.

[0029] a deposition chamber (not shown), in which a substrate is disposed, for receiving the precursor vapor and depositing the precursor vapor on the substrate;

[0030] The flow control valve 11 is located between the vaporization device 10 and the deposition chamber. The precursor vapor flows into the deposition chamber through the flow control valve 11, which is used to adjust the gas supply flow of the precursor vapor. Before the vaporization device transports the precursor vapor to the deposition chamber, the valve is closed for 2 seconds and then opened again.

[0031] The flow control valve 11 is a three-way valve, and the input end of the flow control valve 11 is connected to the gasification device 10;

[0032] The nozzle 12 is connected to the deposition chamber, and the first output end of the flow control valve 11 is connected to the nozzle 12;

[0033] An air pump 13 connected to a second output end of the flow control valve 11;

[0034] The exhaust device 14 is connected to the air pump 13 .

[0035] In addition, the device may also include a single-chamber type, a cluster type, a furnace tube type, and a flip type (not shown in the figure). Since they do not involve the invention point, they will not be described in detail in this embodiment.

[0036] The apparatus and method in the embodiments of the present application can be used to deliver atomic layer deposition vapor to manufacture semiconductor devices such as DRAM, Flash (planar, 3D NAND) and LCD by thin film deposition of materials. The apparatus 100 can assist in making etching and deposition uniform, thereby improving the quality of the film. Although the apparatus is described in the context of an atomic layer deposition process, the apparatus can be applied to other deposition processes.

[0037] Furthermore, the semiconductor device manufactured by the apparatus and method of the embodiments of the present application can be used in various chips.

[0038] Furthermore, the chip having the above-mentioned semiconductor device can be used in various electronic devices. Specifically, the electronic device can be a smart phone, a computer, a tablet computer, a wearable smart device, an artificial intelligence device, a mobile power supply, etc.

[0039] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0040] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, a person skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A method for forming a film on a substrate surface, characterized in that: The following steps are involved: vaporizing the precursor into precursor vapor using a vaporization device; Using a deposition chamber to receive the precursor vapor; A flow control valve is arranged between the gasification device and the deposition chamber, and the precursor vapor flows into the deposition chamber via the flow control valve. During the process of conveying the precursor vapor into the deposition chamber, the flow control valve is closed for 1-3 seconds and then opened again, so as to increase the gas supply flow rate of the precursor vapor by compressing and then expanding it, so as to form a film with uniform thickness on the substrate surface of the deposition chamber.

2. The method for forming a film on a substrate surface according to claim 1, characterized in that: The precursor vapor is formed on the substrate in an atomic layer deposition manner.

3. The method for forming a film on a substrate surface according to claim 2, characterized in that: The material of the film is selected from any one component or a combination of multiple components of HfO2, ZrO2, TiO2, Nb2O5, Al2O3 and SiO2.

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